Service switch and fuse mechanism.



J. A. IESSEN.

SERVICE SWITCH AND FUSE MECHANISM. APPLICATION FILED JULY 16. I914.1,209,445. Patented Dec.19,1916.

UNITED STATES PATENT OFFICE.

JOHN A. JESSEN, OF WINTHROP, MASSACHUSETTS, ASSIGNOR TO THE PALMER ELEC-TRIO & MAN UFACTUBING COMPANY, OF BOSTON, MASSACHUSETTS, A CORPORATIONOF MAINE.

Specification of Letters Patent.

Patented Dec. 19, 1916.

Application filed July 16, 1914. Serial No. 851,295.

To all whom it may concern:

Be it known that I, JOHN A. JESSEN, a subject of the King of Denmark,and a resident of I'Vinthrop, in the county of Suffolk and State ofMassachusetts, have invented certain new and useful Improvements inService Switch and Fuse Mechanism, of which the following is aspecification.

The object'of this invention is to produce a combination switch andthermal cutout or fuse mounted in a box or casing adapted to be closedor secured by a seal to prevent unauthorized access to thecurrent-carrying parts, and in which, without breaking the seal, theswitch may be manipulated to open or close the circuit or the fuses maybe exposed for inspection or replacement without breaking the seal, or,by breaking the seal, the switch and fuse members may be inspected inthe normal position they occupy when the switch is closed and the fusesare actively in circuit with the electrical connections of the box.

A further object of the invention is to provide a device in which theopening of the switch does not necessarily expose either the fuses orany part of the switching mechanism, thus preventing an accumulation ofdust in the box when the switch is left in an open position.

In the embodiment of my invention as illustrated on the drawings andhereafter described, in detail, when the fuses are brought to theposition in which they may be inspected or replaced without exposing anycurrent-carrying parts, the movable switching members and fuse contactsare entirely disconnected from the fixed contacts which connect with themain and load terminals, making it impossible under these conditions foran operator to come in contact with any current-carrying parts andpreventing access to current-carrying parts by persons who have noauthority to break the protecting seal of the box.

\Vhen the switch has been opened, the fuses may be exposed by themovement of a shield or door which must be moved to conceal the fusesbefore the switch is again. closed. When the seal cover has beenremoved, it is impossible to replace same with the shield or dooroccupying a position that would permit access to the fuses while inactive position.

On the accompanying drawings,-Figure 1 represents a plan view of aswitch and fuse box embodying my invention. Fig. 2 represents a similarview with the cover removed. Fig. 3 represents a side elevation of thesame. Fig. 4 represents a section on the line 14 of Fig. 1. section onthe line 5-5 of Fig. 1. Fig. 6 represents a longitudinal section on theline 66 of Fig. 1. Fig. 7 represents a cross section with the movableswitch removed. Fig. 8 shows the cOVer in perspective.

I desire to have it understood that theinvention is capable of manyembodiments, and that there is no intention, by the followingdescription of the details of construction of the switch and fuse boxillustrated in the drawings, to limit the invention to such details.

The main body ofthe box orcasing 10 i may be'of any suitable shape andmade of any desirable material. As shown, it is made of sheet metal andis rectangular in plan view, with a bottom wall 11, side walls 12, 12having apertures for receiving con duits and bushings for the main andbranch circuit conductors, and end walls 13, 14. The box is closed by acover 15, which is shown as wholly removable, though it might be hingedat one edge if desired. As illustrated, the cover has marginal flangesoverlapping the side and end walls of the box. An aperture 16 is formedin the flange at one end of the cover to receive a pin 17 riveted to theend wall 13 of the box, and an aperture 18 is formed in the cover toreceive an upstanding ear or lug 19 formed on or secured to the end wall1 1 of the box. A sealed wire 20 passed through the lug or ear 19securely locks or seals the cover against removal by unauthorizedpersons.

In the box I place parallel separated blocks 21, 21 of insulatingmaterial on which are mouted the stationary contacts 22, 23, 24 and 25of any convenient or desirable design. The contacts on one block areelectrically connected with the meter or load circuit and may be calledbranch contacts, while the main contacts on the other block areconnected with the main circuit. A movable carrier or switch, carryingcontacts complemental to those hereinbefore referred to, is located inthe box. It comprises a block 26 of insulating material arranged toslide Fig. 5 represents a cross' lid between the blocks 21, 21. Asshown, it may with convenience be secured upon a slide 2'? resting uponthe bottom plate of the box and limited in its sliding movement byheaded screws 28, 28 passed through a longitudinal slot therein. Theblock is secured to the slide in any convenient way, the face thereofare secured the movable contacts 29, 30, 31 and 32, those at 29 and 30being complemental to those at 22 and 23 and those at 31 and 32 beingcomplemental to those at 24 and 25. Electrically connected to thecontact 25 is a socket 33 for a fuse plug, there being a like socket 34connected to the contact 30. To the contacts 31 and 29 are electricallyconnected metallic strips 35, 36 beneath the sockets to be engaged bythe v ends of the fuse blocks. lhe insulating slide the slide. formed ofresilient -moved to the left in Fi depress the knob 46,

or carrier 26 is formed integrally or provided with an upstanding flangeor wall 40 of insulating material for inclosing the fuse plugs 41 and42, and the exterior of which is oblong in plan view. These plugs areseparatedfrom each other by a partition 43' extending across the recessin the inclosing wall d0. When the switch is in its closed position, asshown in Fig. 2, an electric circuit is afi'orded from the stationarycontact 22 to the stationary contact 23 through the movable contacts 29and 30 and the associated fuse 42. In like manner, a circuit is closedfrom contacts 24: to 25 through contacts 31, 32 and the associated fuse4:2.

A handle 44: is secured to the slide 27 and projects through an aperture45 in the end wall 13. 0n Its projecting end the handle has a knob 46 bywhich it may be manipulated, and it carries'inside of the box a stop 47for limiting the outward movement of The handle 44: is preferablymaterial and it is curved u wardly'as shown in Fig. 4:, being provldedwith a shoulder or latch 48 which normally engages the wall 13 at theend of the slot 45, thereby to lock the switch in closed position.Bydepressing the handleuntil the latch 48 is disen aged from the endwall of the slot, the handle may be 4 to 0 en the switch. ll preferablyprovi e means or preventing the switch from being moved to partiallyclosed position. Said means comprises a spring 50 interposed between theslide 27 and the end wall 14 of the box. For convenience, said spring iscoiled about a horizontal post 51. In order to open the switch thereforeit is merely necessary to whereupon the spring 50 will automaticallyopen the switch, but said spring will also automatically return theswitch to open position unless it be moved inwardly far enough for thelatch 48 on the handle 44: to interlock with the end wall of the box.

As indicated in the first part of this speciand upon neonate fication, 1provide a shield or door which prevents access to the fuses when theswitch is closed, but which may be moved to expose the fuses when theswitch is open, Said shield is so arranged and mounted that the switchcannot be closed until the shield has been moved to closed position torender the fuse plugs inaccessible. To this end, the cover 15 isprovided with an aperture 52 so located as to register with or bedirectly above the fuses when the switch is open, as shown in Figs. 1and 4. Beneath the opening, there is arranged a sliding shield or door53. Transverse guideways 54, affixed to the under side of the box cover15 and underlapping theends of the shield, guide said shield in itslateral movement to close and open the aperture. Said shield is providedwith an upstanding post 55, which, when the seal is closed, is in closeproximity to the upstanding ear or lug on the cover near the side wallof the aperture 52. The

parallel with the adjacent side of the wall 40 of the carrier whichincloses the fuses, and that, when the switch is closed, the said walllies in the path of the said member so that the shield cannot be opened.When the switch is moved to open position, however,

as shown in Fig. .6, the wall 40 is moved a short distance out of thepath of the member so that the slide may be freely moved to the right inFig. 1. 'When the slide is open, however, the said member is locateddirectly in the path of the switch,-that is, is so placed as to beengaged by the end of the part 40, whereby the switch cannot be closeduntil the shield has been first returned to its closed position.

From this description, it will be apparent that an inspector or a dulyauthorized person may, by breaking the seal 18,- remove the main cover15 and inspect the fuses in their working positions without breaking thecircuit. When, however, the main cover is closed and sealed, it isimpossible for anyone to obtain access to the current-carrying parts atany time and impossible to obtain access to the fuses without firstopening the switch, and, after the switch is open and the fuses havebeen inspected or replaced, it is impossible to close the switch withoutfirst closing the shield. I thus provide the cover and the switch withwhereby the shield cannot be opened without previously opening theswitch, and the switch cannot be closed without previously closing theshield.

interlocking means fuses, I may employ link fuses and that various otherchanges may be made without departing from the spirit and scope of theinvention.

Having thus explained the nature of my said invention and described away of making and using the same, although without attempting to setforth all of the forms in which it may be made or all of the modes ofits use, what I claim is:

l. A box, a movable carrier, a fuse thereon and movable by the carrierfromelectrically active position to electrically inactive position, amovable shield for the fuse registering with the fuse only when saidfuse is in said active position, and means for locking said shieldagainst movement when the fuse is in electrically active position, andunlocking said shield when the fuse is in said inactive position.

2. A box, a cover therefor, a fuse, a fuse carrier movable to locate thefuse in active and inactive positions, said cover having an opening forexposing said fuse, a movable shield normally closing said opening, andinterlocking means between said carrier and said shield to lock theshield against movement except when the fuse is in its inactiveposition.

3. A box, a cover therefor, a fuse, a fuse carrier movable to locate thefuse in active and inactive positions, said cover having an opening forexposing said fuse, a movable shield normally closing said opening, andinterlocking means between said carrier and said shield to lock theshield closed when the fuse is in active position and to lock the fusecarrier with the fuse in inactive position when the shield is in openposition.

4. A switch box, a cover therefor having 0 an opening, a sliding shieldfor closing the opening, a switch and an associated fuse movable intoopen andclosed positions, and a member on said shield arranged to engagethe switch and hold the shield closed when the switch and fuse are inactive position.

5. A switch box, a cover therefor having an opening, a sliding shieldfor closing the opening, a switch and an associated fuse 5o movable intoopen and closed positions, and a member on said shield arranged to standin the path of closing movement of the switch when said shield is open,to prevent closing of the switch when the shield is open.

6. A switch box, a cover therefor, stationary contacts in said box andrendered inaccessible by said cover, a movable carrier, contacts and anassociated fuse on said carrier,

means for moving said carrier to open and closed positions, said coverhaving an opening for permitting access to the fuse, a movable shieldsupported by the cover for closing the opening therein, and means bywhich the carrier locks the shield shut when the WM. L. HATFHILD G. W.PUTNAM.

